You can read the requirements yourself. It spells out very clearly what's needed from both the player and the league. I had to look into a P-1A visa last summer, for my own work an official in another sport, so while not a lawyer, I do have some recent experience in this area. Standard processing time is 2-4 months but you can pay extra to have a premium processing, in which case it's about 3 weeks. He would have had a work visa when he was with the Packers (since he got paid for his brief time there) but that would have been tied to his contract with them. There is a window where he would have been able to get on with another team and the visa would be valid but it's only for 60-90 days so he'd need a new one for the UFL. The issue is getting a new one and whether or not the UFL qualifies. P-1A Athlete | USCIS For Internationally Recognized Individuals or Teams You must submit a copy of a tendered contract with a major U.S. sports league or team, or in an individual sport commensurate with international recognition in the sport, if such contracts are normally utilized in the sport, and documentation of at least two of the following: Evidence of having participated to a significant extent in a prior season with a major United States sports league; Evidence of having participated in international competition with a national team; Evidence of having participated to a significant extent in a prior season for a U.S. college or university in intercollegiate competition; A written statement from an official of the governing body of the sport which details how you or your team is internationally recognized; A written statement from a member of the sports media or a recognized expert in the sport which details how you or your team is internationally recognized; Evidence that you or your team is ranked, if the sport has international rankings; or Evidence that you or your team has received a significant honor or award in the sport. You must be coming to the United States to be employed as an athlete by: A team that is a member of an association of six or more professional sports teams whose total combined revenues exceed $10 million per year. The association must govern the conduct of its members and regulate the contests and exhibitions in which its member teams regularly engage